Texas schools are fast becoming the front line in a culture war being waged by America’s religious right.

A Texas education authority became the state’s 49th to pass a measure to teach Bible lessons in its secondary schools at a raucous meeting late last month that at times resembled a church gathering.

Supporters prayed and sang hymns outside and packed the inside of the meeting of the Ector county school board in Odessa, which voted 6-0 to offer “biblical literacy” classes. A local activist had presented officials with a 6,000-signature petition in support of adding Bible study to the curriculum.

“There’s a gap in the education of students, and people have been wondering what’s missing,” said Elizabeth Ridenour, president of the National Council on Bible Curriculum in Public Schools, which produces a Bible study course used in around 11,000 US schools, and which helped mobilise the campaign in Odessa.

“Unless you have a working knowledge of the Bible it’s difficult to understand the basis of the US constitution - most of our founding documents are based on it,” Ms Ridenour said.

“How could you understand what’s going on in the Middle East without incorporating knowledge of the Bible?” she added.

The year-long course, entitled “The Bible in History and Literature”, uses the Bible as a textbook, Ms Ridenour said.

The council, supported by a prominent US “televangelist” and endorsed in television advertising by martial arts legend Chuck Norris, is in talks with between 30 and 35 education authorities interested in its courses.“It’s beginning to snowball,” Ms Ridenour said.

Ector county school district superintendent Wendell Sollis said the optional course would be strictly academic, shunning “devotional” content.

Officials have yet to decide whether to adopt the course offered by Ms Ridenour’s group, which contains strict guidelines instructing staff to avoid indoctrination. But critics remain unconvinced that the Bible courses are anything more than a vehicle for Christian evangelism.

Earlier this year, education chiefs in Frankenmuth, Michigan, rejected the council’s course after a year-long debate, saying it lacked academic merit and crossed over into religious proselytising. Ms Ridenour said officials there had an old, outdated version.

Bible instruction is just one of a number of school issues being targeted by US religious conservatives, including organised prayer, the teaching of Christian alternatives to evolution and abstinence-only sex education.